Qaidam Basin, also spelled Tsaidam (Mongolian: Цайдам, from Standard Tibetan: ཚྭའི་འདམ་,"salt marsh"; simplified Chinese: 柴达木盆地; traditional Chinese: 柴達木盆地; pinyin: Cháidámù Péndì) is an hyperarid basin that occupies a large part of the Haixi Mongol and Tibetan Autonomous Prefecture in Qinghai Province, western China. The basin covers an area of approximately 120,000 km², one fourth of which is covered by saline lakes and playas. By one count, there are 27 such lakes in the basin. Around 35,000 square kilometers, or one third of the basin is desert, which is known in Chinese as Chaidamu Pendi Shamo (柴达木盆地沙漠), i.e.